Clutch operating mechanism



Sept. 27, 1938. R, s. SA FORD 2,131,075

CLUTCH OPERATING MECHANI SM Filed Sept. 2'7, 1935 3 Sheets-Sheet 1 BY Macaw i 8 N F99 Sanford ATTORNEYS.

Sept. 27, 1938. R. s. SANFORD CLUTCH OPERATING MECHANISM Filed Sept. 27, 1955 3 Sheets-Sheet 2 INVENTOR.

R2 1 5'- Jan 0rd p 1938- R. s. SANFORD CLUTCH OPERATING MECHANISM Filed Sept. 27, 1935 5 Sheets-Sheet 3 INVENTOR. 52y 1.5. Sanjcrd BY /7 0' ATTORNEY5 n L z.

Patented Sept. 21,1933

cw'ron ornaa'rmo MECHANISM Roy S. Sanford, New York, N. Y., assignor to Bendix Products Corporation, South Bend,

Ind., a corporation of Indiana Application September 27, ,1935, Serial lilo. 42,418

My invention relates to automotive control mechanism and has particular reference to a power operated clutch and free wheeling unit. 7 An object of the inventionis to associate the conventional clutch actuating mechanism and the ordinary free wheeling unit installed rearwardly of the transmission with a vacuum system operable automatically in conjunction with manipulation of the accelerator pedal controlling the engine speed. The engine is de-clutched from the drive shaft and the free wheeling unit is brought into play automatically upon releasing the acceleratorpedal to relieve both ends of the transmission mechanism of load, such relief at each end permitting rapid manipulation of the gear shift mechanism without clash. Means are provided whereby the free wheeling unit may be retained in free wheeling position if desired, the vacuum lines and controls therefor being adapted to govern this phase of the system through manual'manipulation of a hand lever placed upon the dash of the vehicle.

A further object of the invention is to incorporate with the power mechanism associated with the clutch actuating means an improved bleed valve whereby upon depression of the accelerator pedalthe exhaust portion of the cylinder is first rapidly vented to air and subsequently restricted as to the volume and rate ofair outlet for-the purpose of insuring a gradual engagement of the clutch unit by cushioning the movement of the piston in the power cylinder.

Another object of -the invention resides in the provision of a vacuum servo valve associated with the accelerator pedal in such manner that it operates automatically when no longer restrained by the accelerator. An important feature of the 1 cylinder,

Fig. 1 is a somewhat diag of the complete system,

Fig. 2 is a plan view of the free wheeling unitand its power operating means, partly in section,

Fig. 3 is a section through the manually opeenable dash control free wheeling valve, I

Fig. 4 is a section illustratingthe mechanism for actuating said valve,

Fig. 5' is a section through my improved servo vacuum control valve, V A Fig. 6 is asection throughmy improved-cushioning valve,

Fig. 7 is an elevation, partly in section, illustrating the air vent in the clutch operating power c, illustration.

Fig. 8 is a section through a modified valve similar in its function to that 'orFlg. 5, illustrating the parts in accelerator =-released'position, and

Fig. 9 is a section illustrating the valve of Fig. 8 as positioned when the accelerator is normally depressed.

Referring now to the diagrammatic illustration of Fig. 1, the system comprises an internal combustion engine Ill provided :with a conventional intake manifold l2 having a carburettor l4 associated therewith. Throttle control arms '16 and it are retained in motor idling position by means of a spring 20 and the arms are'connected tohand actuated throttlerod' 22 and acceleratorrod 24 respectively through the lost motion connections indicated at 26 and 28.

improved control resides in the servo feature of the valve whereby slight movement of the primarycontrol element automatically causes a substantial movement of the secondary valve, which secondary valve operates to open and close certain of the vacuum lines associated with the vehicle control mechanism. It is desirable to r utilize as little mechanically actuated movement as possible in controlling the vacuum lines, but at the same time substantial movementv is often essential in order to provide for the various port controls essential to satisfactory operation.

Various other meritorious features will be apparent from the followingdescription taken in conjunction withthe drawings wherein like numerals refer to like parts throughout the several figures and wherein:

v A transmission 30 is positioned behind the clutch mechanism 32 and a free wheeling unit 34 is mounted rearwardly of the transmission. A lever 36 functions to draw the free wheeling unit into locked out position or free wheeling position. The clutch actuating arm 38 is pivotally connected to the extremity of piston rod 40 and is in this. manner'operated by the piston 42 positioned in the clutch operating power cylinder 44. The arm 36 is connected in similar manner to piston 46 in free wheeling-power operator 48, this piston being normally positioned at one extremity of the cylinder by means of a spring 50, which spring functions to retain the arm 36 in position to hold the free wheeling unit in locked out position.

One end of a clutch operating power cylinder 44 is connected through conduit. 52 with my improved vacuum control valve 54, this conduit being provided with "a branch conduit 56 which opensfinto the valve chamber of the free wheeling control valve 58. The opposite extremity of the clutch operating cylinder communicates with the provided at its exhaust endwitha one-way ventvaive clearly illustrated in Fig. 7 and comprising a spring actuated valve member 04 operating to close vents 00 against the outward passage of .air but permitting inward flow therethrough.

The free wheeling power cylinder 40 is-provided with an air vent 00. at its exhaust end and g the other communicates'with a vacuum line 10 which opens into the chamber. of free wheeling control valve 00. The intake manifold I2 communicates with the chamber of control valve 04' through a conduit II, which conduit is provided with a branch line 'l4' opening into the cham-'- ber of. free wheeling'control' valve 00.

Referring now more particularly ,to the con-f tstruction of: the improved servo valve 04 illustrated in detail in Fig. 5, the valve chamber 10, is provided with a shoulder 10 against which a slidable spool valve 80 is adapted to seat, thus limiting the rearward movement of said valve.

A conduit 02 connects the opposite extremities of valve chamber" through ports 04 and 00 provided therefor. The valve casing is provided with a longitudinal passage 08 which communicates through port 90 with the rear end 'of the valve chamber, thereby providing a passage from said end to the valve port 9| which is connected directly to the vacuum conduit I2 extending .to

the intake manifold.

Valve 80 is provided with an axial bore adapted to slidably receive a cylindrical valve 92 which is of slightly greater length than the spool valve 00 and provided with stop heads 93' at each end thereof, as clearly illustrated. The cylindrical valve 92 is provided with a groove 94 adapted to register with port 96 in the forward head of the spool v'alve. Port 90 opens into an annular groove 95 extending around. the, circumference of the head of said spool valve. The groove 94 is provided with a transverse bore 90 communieating with an. axial bore I00 which extends through the valve 02 from the groove 94 and opens into the rear end of the main valve chamber I0. Groove 95 is'adapted to register with air port 91 on the valve casing.

Slidable axially through the rear end of'the valve casing 54 is a plunger I02. One extremity of this plunger forms a secondary valve I04 slidable within the rear end of the valve chamber 10 and operable on initial axial movement to close the port 90. Rearward movement of the plunger and secondary valve I04 is limited by abutment of the restrictedrear portion I00 .01? .the said valve against the end of the valve casing. When the plunger I02 is in the position illustrated in Fig. 5, wherein the accelerator pedal isreleased, air will flow through passage I08 and through the conduit 02- to the forward, end of the valve chamber 16. .,In this position the rear endof the valve chamber is in communication with the vacuum conduit I2 through port 90 and for that reason the spool valve 80 'will be moved or retained in or to the positionillustrated in Fig. 5. The cylindrical valve 92 will also be retained in the position illustrated. When the parts are in this position it will be apparent that-the line 52 to the clutch operating-cylinder 44 is open to vacuum conduit I2. 1

The accelerator rod 24 has secured thereto a 2,181,015 cushion valve 00 through avacuum conduit 02;

oi-plunger I02 against the bracket 0. It will be noted that the valve 04 and the connecting conduit between the ends of the valve chamber. I0 are broken away .inl'ig. 5. The actual proportions and relative spacing between valve ports, et cetera, is more clearly indicated in Figs.

8 and 9 whereina modified form of valve structure-is As already stated, the valve mechanism in Fig.

5 has been illustrated as in the position occupied when the accelerator pedal is released. It

will be noted that the port 0|, is in-communication with conduit 02 through the cut away portion' 00' of spool valve -00, thereby establishing a vacuum in the clutch'operating cylinder 44 to der-clutch the engine. Upon initial depression'of .the'accelerator pedal the bracket 0 will-move .plunger I02- forwardly, the spring 0 being of 'a"strength which is suflicient to; prevent yielding thereof at any stage of operation. At this point the admission of air through the passageway ill will be closed and theport "will be closed simultaneously to stop active maintenance ofvacuumin the rear end of the valve. chamber 10. Further movement of plunger I02 will open the forward endof valve chamber I0 to the suction in line I2 through conduit 02 and port 00, there-. by eliminating the air in the forward portion of.

valve chamber I0 and creating a positive vacuum there. Forward movement'of piston I04 will uum is created. in valve chamber 10 at its forward'end at this stage of the operation, producing a partial vacuum as distinguished from a positive vacuum. at the rear end of the cylindrical valve :92 it will be forced axially through the spool valve 80 to open the. air port 91 to groove 94 and axial passage I00 of the said cylindrical valve. In this way air is admitted to the rear end of valve chamber I0 andthe entire spool valvev is'slapped rapidly i'orwardto close the port 9i. When the spool valve has reached the extreme forward limit of its movement port 90 will be closed but the forward head of the valve will have opened the airport 91 in the valve casing to communication with conduit 02 extending to the clutch operating cylinder 44. -At this point'a release movement of piston 42 begins. Release movement of piston 42 ispermitted by open air vents in the head of the booster cylinder 44 and is controlled by an improved cushion valve 00 clearly illustrated in Fig. 6. The action thus described takes place upon the initial depression of the accelerator pedal which actuates the rod 24. The bracket 1 I0 secured to rod 24 is provided with a downwardly extending arm I20 which is positively connectedwith the stem 122 of valve I24 which is slidable within thev'alve casing 00. As clearly illustrated in Fig. 1 the vented. end of booster cylinder 44 is connected through'conduit 02 and the valve port I20 with the valve 00. Upon depression of the accelerator pedal the operation heretofore described takes place. rear end of the. power cylinder 44 is ventedto The the atmosphere through valve l 4fand conduit is;

As the piston 42 moves forwardly'the' air on the haust of the air from the cylinder is closed at substantiallythe point where depression of the accelerator has taken'up the lost motion provided by the lost motion connection through which the carburettor valve is actuated.

1 At "this point the air forwardly f the among: is compressed in the forward end of 'the power v cylinder sufficiently to counterbalance the action of the clutch springs. preventing actual enga'ge ment of the clutch plates. At. this point the valve I24 in the bleed valve casing 50 begins to open haust of the compressed air at the forward end of the power cylinder. The valve ports I28 and I28 and the valve member 124 maybe so positionedand shaped that the said ports I28 and I28 will gradually create an increasing exhaust pas:

sage for the power cylinder at any point during the depression of the accelerator pedal.

If the accelerator pedal is gradually depressed I to raise the motor speed when a gradual acceler I ation of the car is desired, the opening of the ports I25 and I28 will be correspondingly gradual, thereby insuring gradual engagement of the clutch through slow movement of the booster piston 42. I If-the accelerator is depressed sharply it is obvious that the motor speed will be brought rapidly up and the valve I24 is so tapered, as indicated at I30, that a maximum exhaust of air is permitted; thereby providing rapid engagement of the clutch which may be con-' venientlyhandled by the increased R. P. M. of the motor at that stage of accelerator depression.

The travel of the va1ve'I24 corresponds to the the particular shape ofthe valve I24, including the taper It and the reverse taper I80, a grad ual exhaust of air is insured when the accelerator pedal is depressed sufficiently to increase the R. P. M. of the motor only slightly and also when the accelerator pedal is sharply depressed, as

when a rapid gear shift is made at a consider.- able speed. This latter action is desirable forthe to catch up to the R. P. M. of the drive shaft in order to eliminate Y jerky engagemgit of the clutch.

Returning now to control of the free wheelin unit '34, movement of spool valve I34 in free wheeling control valve 58 is secured by a'link I35 connected to the projecting stem I38 of said valve, which link is pivotally secured to an arm I40. Arm I40 is fixedly secured to the extremity of a shaft I42 rotatably journalled in thedash panel I44 and to the other extremity of shaft I42 issecured a manually operable lever I46. A clutch collar I48 is rotatable with shaft I42 and slidable therealong through a pin and slot connection indicated at I50. Spring I52 urges the said collar I48,into engagement with a cooperating clutch panel as by screws I55. The valve I34 may be actuated therefore through lever I45 and retained in either-free wheeling or locked out position.

The drawings illustrate the various control mechanisms in position to maintain free wheeling constantly during operation of. the vehicle. Under such circumstances valve ports I58 and I50 of free wheeling control valve 58 are in communication and a vacuum is constantly maintained through conduits I4 and II to the free wheeling when the valve I84 is shifted by means of lever I40 this direct vacuum communication'is closed and communication is established between-port 150' and port I82, the latter being connected to the conduit I8. Under such circumstances free :wheeling unit 84 will normally be retained in locked out position through spring 50 in the booster '48. However, when the vacuum conduit 82 is open to create vacuum in clutch power cylinder. 44 it will also operatethrough line 58, valve "58, and conduit 10 to actuate piston 48 of the a the ports I25 and I20 toprovide for further exf freewheeling powerv cylinder to. automatically only upon release of the accelerator, at which time the clutch power cylinder operatesto declutch the engine and the result will be to unload both ends of the transmission mechanism 80 whereby easy gear shifting without clash may be secured.

In Figs.'8 and 9 a modified form of control valve 54 hasbeen illustrated in its two extreme limits of movement. This valve is the same in every way as that illustrated in Fig. 5 with the exception of the fact that the servo valve I80,

which is mechanically actuatedthrough the accelerator rod 24, provides means for admitting air momentarily into the rearward portion of the valve chamber 15. In this way the vacuum established in the forward portion of the valve chamber cooperates with the normal atmospheric-pressure thus admitted to the other end of the chamber to actuate the cylindrical valve 4 82' rather than with a partial vacuum, as with travel of the accelerator pedal and by reason of the structure of Fig. 5.

' Describing the structure somewhat more in detail, it will be noted that the rear end of the valve casing 54' projects some distance rearthrow the free wheeling unit 04 into freewheeling position, Obviously this action will occur wardlyas indicated at I82, the valve stem I02 beingv slidable therein as in the Other structure. Upon initial depression of the accelerator pedal the stem I02 will be.urged forwardly to first close the rear portion of the valve chamber I5 purpose of permitting the R. P. M. of the motor from the vacuum line I2 by closing the port 80*.

; As the head of the servo valve I80 passes the will be momentarily vented to air through the longitudinal passageway I84 which communicates through transverse'port I88 at its rear extremity with the air vent I88. This momentary admission of air ahead of the servo valve I80 at the time when the forward portion ofthe valve chamber I5 is substantially evacuated operates to force the cylindrical valve 82' axially through the spool valve 80 to permit the passage of air through 'the air port 81' to the rear portion'of the valve chamber, thus maintaining the differential pressure between the forward and rearward ends of the chamber to force the spool valve 80' to its fo'rward limit of movement.

As clearly indicated in Fig. 8 the forward portion of the valve chamber is opened to atmospheric pressure through the connecting conduit 82' and the longitudinal passage I08 in the valve stem I02 when the accelerator is in its released position. Fig. 9 illustrates the position of the valve members when the accelerator is fully depressed for driving purposes, the line 52' having been vented to air through port-'81 and cut of! completely from the vacuum in line 12'. I

While certain preferred structures have been illustrated in the accompanying drawings various modified forms willbe apparent to those skilled in the art and for that reason'I wish to limit myself only} within the scope of the append ed claims:

I claim:

1. Valve mechanism including a cylindrical chamber-shouldered intermediate its ends, a vacuum operated spool valve slidable within the same on one side of said shoulder, means placing the ends of the chamber in fluid-transmitting connection and avalve having a stem extending through the end of the valve easing on the other side of said shoulder.

2. Valve mechanism including a cylindrical casing having a shoulder intermediate its ends. a spool valve slidable within said chamber onv one side of said shouldered portioma cylindrical valve of greater length thansaid spool valve slidable axially through said spool valve and including stop heads, at each extremity thereof, and a secondary valve slidable within said chamber slidable within said chamber intermediate the extremities thereof, and a valve member slidable within said chamberat one extremity thereof,

said valve including the vent providing communication between the atmosphere and one end of said connecting conduit when said valve is at one limit of its movement, said ,valve being operable on initial movement thereof to 'close said air communicatior'i.

4'.In combination with a vacuum source, a valve chamber. anda valve member slidable therein, 'a conduit connecting the end portions I of said valve chamber, and a valve member positioned within said chamber normally operable to vent one end of said valve to the atmosphere and operable upon initialactuation thereof to close said vent and open the vacuum source to communication with said aforementioned end of the valve.

ROY S. SANFORD. 

